| The surveying and mapping satellite is the main technology means to acquire the outer-boundary targets' space information.In order to complement the photographic position satellites' targets' position without ground control conditions,Simultaneity when the satellite photographs the ground,it must shoot the star and then after the process of the star's image can acquire the attitude and angle elements of the ground photo's instant photography.And these attitude data will be important in controlling in the satellite photogrammetry position:effectively suppressing the system errors' accumulation,or without ground controls, being used with the orbit data,by constructing photogrammetry controlling grid and the block adjustment calculation,it can achieve the assignment that accurately survey the target points and control the grid points' coordinates.It is possible to do the big block adjustment calculation.The photo attitude's computed principle is the double vectors attitude principle and the photogrammetry's collinear equation.Through the followed steps it can get the photo's attitudes and angles:through the star's image coordinates which is acquired from accurately surveyed,after analytical orientation,normalizing the stellar points' coordinates to the collimating mark coordinate system;By the rapid looking for star algorithms getting the correspondent star's celestial coordinates from the star catalogs database,then normalizing the star's apparent place by the standard epoch. Applying the normalized stellar points' coordinates and the correspondent star celestial coordinates (normalized by the apparent place),then constituting the error equations by the co-linearity equations, it can solve the photo's attitude angle of the instant photographic.By constructing the satellite-ground camera's space data conversion model,determining the ground photo's attitudes and angles,it can offer high accurate attitude data for the photogrammetry and position satellites.The major progenies and conclusions are generalized as follows:(1)Utilizing the image process technology to automatically recognize the star photo collimating mark points and the stellar points and accurately survey the photo coordinates,at last solving out the problem that the automatic recognizing and surveying of the star photo collimating mark points and the stellar points.(2)According to the vector surveying principle,constituting a high accuracy stellar photo's attitude computation model,and synthetically utilizing J2000 star catalogs database and the star apparent place's computation methods,making the capacity of the star recognition improved,simultaneity obviously increasing the computation accuracy and reliability of the stellar photos' attitude.(3)Researching the rapid and practical automatic looking for stars algorithms,by the stellar's surveying coordinates,applying rapid looking for algorithms,it can find the correspondent star of the stellar sieving from star catalogs database's 1000 thousands of records.(4)Constituting the stellar cameras' space data conversion model,in researches and develops the satellite photo's attitude computation system based on the digital image.(5)Practically processing 63 pieces of star images,the quantity of the recognized stellar is many and uniform distribution,it is content for the index requirement of the total reliability and total accuracy,the attitude angle's average accuracy is m_α,m_δ≤0.8″,m_κ≤5″.(6)When the satellite photo attitude data applied in the satellite photo aerial triangulation's densification results,it can draw a conclusion that the densification accuracy is better with photo attitude angle control than without photo attitude angle control,especially it indicates that the photo attitude angle can effectively eliminate the system errors' accumulation and increase the whole accuracy. |
